Prior or simultaneous addition of ammonium sulphate can, not only enhance the activating effect of hydrosulphide ions on xanthate flotation of malachite but it can also eliminate possible detrimental or depressing effects of excess residual hydrosulphide. Use of relatively inexpensive ammonium sulphate appears to reduce the consumption of the much more expensive sulphidizing agent for optimal flotation recovery.

The mineralogical studies done on Hope Brook ore samples indicated that a heap leach gold recovery process may be possible. In the metallurgical program that followed, column tests confirmed this interpretation. A 9300 tonne demonstration heap leach test, in the late fall of 1985, reaffirmed laboratory results while identifying operating conditions that will have to be addressed in a production heap leach plan. Operating plans, gold recoveries and cost areas will be presented.Another...

Once all the hullabaloo about Finance Minister Wilson's April 27 budget died down (or was it an April 26 budget?), the pain of the budget papers began to sink in. Individuals and corporations will have to dig deeper and pay more taxes &mdash; and government will continue to dig deeper and spend more. The irony of the situation is that higher tax rates actually make flow-through shares more attractive as a tax-deferral investment &mdash; a bittersweet &quot;bravo&quot; for the mining industry.

Stillwater Mining Company (SMC), a partnership of Chevron Resources and Manville Corporation, produces a copper-nickel, platinum-palladium flotation concentrate at its Nye, Montana mine. The concentrate is then toll processed in Europe. Recognizing the economic advantage of treating the concentrates at the mine site and of retaining this strategic resource in the United States, the Company commissioned Tolltreck International Limited and International Process Research Corporation to conduct...

The mine operator has two prime objectives when he operates a mine: (1) the mine must be safe, and (2) the mine must operate with the lowest possible costs. The operator constantly faces a dilemma; if he is over cautious with regard to safety, his costs may be very high, and if he is over-zealous in trying to reduce costs, the safety of his operation may be jeopardized.Modern bulk mining methods rely heavily on high productivity non-entry sloping techniques (e.g. open sloping, VCR, etc.)....

The mine operator has two prime objectives when he operates a mine: (1) the mine must be safe, and (2) the mine must operate with the lowest possible costs. The operator constantly faces a dilemma; if he is over cautious with regard to safety, his costs may be very high, and if he is over-zealous in trying to reduce costs, the safety of his operation may be jeopardized.Modern bulk mining methods rely heavily on high productivity non-entry sloping techniques (e.g. open sloping, VCR, etc.)....